XT and XTR sprockets questions

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1. At the Shimano site the rear derailleurs (RD-M960) are specified to
service a 11T minimum sprocket and 34T maximum sprocket and 22T maximum
front difference. All this information is clear to me., but I do not
understand the specification called "Total Capacity", 43T for SGS and 33T
for SG. I understand that SGS (the derailleur with super long arm) can take
up more slack than the SG (long arm) and also handle a larger rear sprocket,
but what does the notation 33T and 43T actually refer to?
2. In all previous groups from Deore to Deore XT there was always a crank
and a front derailleur that could be used with a maximum 48T front sprocket.
On the XTR (M960 series) there seems to be no option to fit a larger than
44T sprocket on the crank and the front derailleur can only service a 46T
sprocket. Is this right or is it something like a FC-M961 crank around the
corner? I will build a cross/hybrid with 700C wheels and 11-34 rear sprocket
and 26-36-48 crank and was considering the XTR group M960. Do I really have
to stick with XT if I shell keep my favorite gear span?

Erik L
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to communicate with me directly, not recommended if you communicate about a
news topic.

Erik Lindeberg <egbl@broadpark.com> wrote:
>1. At the Shimano site the rear derailleurs (RD-M960) are specified to
>service a 11T minimum sprocket and 34T maximum sprocket and 22T maximum
>front difference. All this information is clear to me., but I do not
>understand the specification called "Total Capacity", 43T for SGS and 33T
>for SG. I understand that SGS (the derailleur with super long arm) can take
>up more slack than the SG (long arm) and also handle a larger rear sprocket,
>but what does the notation 33T and 43T actually refer to?

The sum of the difference between the largest and smallest chainrings and
the difference between the largest and smallest sprockets.

This is not a hard restriction; you can use a chain long enough to
acommodate the big-big, and live with the fact that it will rattle in the
small-small - it's not like you want to use it.
--
David Damerell <damerell@chiark.greenend.org.uk> Distortion Field!